JP2002099138A - Image forming device, cartridge, and image formation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device, a cartridge, and an image formation system, which can accurately detect the amount of a developer and notify a user of it to let the user know a proper cartridge replacement time. SOLUTION: The image forming device (100) whose cartridge (B) is attachable/detachable is provided with a developer sealing member (6) which is unsealed at the start of the usage of the cartridge between the developer container (4) of the cartridge and a developing means (5), and information corresponding to the value outputted by a developer remaining amount detecting means (30) in a device main body (A) before the developer sealing member (6) is unsealed is stored in a storage means (20) that the device main body (A) is equipped with.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to an image forming apparatus using an electrophotographic system, and more particularly, to an image forming apparatus using a storage unit mounted on an image forming apparatus main body.
The present invention relates to an image forming apparatus, a cartridge, and an image forming system capable of detecting and notifying the amount of a developer in a cartridge that can be mounted on an apparatus main body, such as a process cartridge and a cartridge-shaped developing device.

Here, as an electrophotographic image forming apparatus, for example, an electrophotographic copying machine, an electrophotographic printer (for example, L
ED printers, laser beam printers, etc.) and electrophotographic facsimile machines.

The cartridge detachably mountable to the main body of the electrophotographic image forming apparatus includes an electrophotographic photosensitive member, charging means for charging the electrophotographic photosensitive member, developing means for supplying a developer to the electrophotographic photosensitive member, and electrophotographic photosensitive member. This means at least one of the cleaning means for cleaning the body. In particular, a process cartridge is one in which at least one of a charging unit, a developing unit, and a cleaning unit, and an electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachable from an electrophotographic image forming apparatus main body. Or, it means that at least the developing means and the electrophotographic photosensitive member are integrally formed into a cartridge, and this cartridge is detachable from the main body of the electrophotographic image forming apparatus.

[0004]

2. Description of the Related Art Conventionally, an electrophotographic image forming apparatus such as an electrophotographic copying machine or a laser beam printer forms a latent image by irradiating an electrophotographic photosensitive member with light corresponding to image information. The image is formed on the recording medium by supplying a developer using a developing unit to visualize the image, and further transferring the image from the photoconductor to the recording medium. A developer container is connected to the developing means, and the developer is consumed by forming an image.

In such an image forming apparatus, an electrophotographic photosensitive member and a process means acting on the electrophotographic photosensitive member are used in order to facilitate replacement of consumables such as an electrophotographic photosensitive member and a developer and maintenance. There is a process cartridge system in which the developing means, the charging means, the cleaning means, the developer accommodating container and the waste developer container are integrated as a process cartridge and can be detachably attached to the image forming apparatus main body. According to this process cartridge system, maintenance of the apparatus can be performed by the user himself without relying on a service person, so that operability can be remarkably improved. Therefore, this process cartridge system is widely used in electrophotographic image forming apparatuses.

For example, in a color image forming apparatus having a plurality of color developing means, the developing means and the developer accommodating container are made into cartridges, and each developing cartridge is detachable from the image forming apparatus and can be individually replaced. Some have done so.

In these cartridge type image forming apparatuses, the user can form an image again by exchanging the cartridge when the developer runs out, for example. Therefore, such an image forming apparatus may include a unit that detects when the developer is consumed and notifies the user of the consumption, that is, a developer amount detecting device.

The developer amount detecting device is capable of detecting the remaining amount of the developer in order to be able to know at any time how much developer can be used for image formation in the cartridge. The detecting means is provided in the cartridge or the image forming apparatus main body. In particular, if not only the user is notified that the developer has run out, but also the amount of the developer can be sequentially detected and reported, the convenience of the user can be further improved.

As the developer remaining amount detecting means, there is an electrostatic capacitance measuring system which includes at least a pair of input side and output side electrodes and detects the amount of developer by measuring the electrostatic capacity between both electrodes. One such method is a plate antenna method. This plate antenna system, for example,
In the case of employing a developing method in which an AC bias is applied to the developer carrying member provided in the developing means to develop a latent image formed on the electrophotographic photosensitive member, a sheet metal serving as an electrode is opposed to the developer carrying member, or Provided at a plurality of other locations, the capacitance between the sheet metal and the developer carrier and between the sheet metal and the sheet metal changes according to the amount of the developer, such as insulating toner. It is a thing that utilizes that.

That is, if the space between the sheet metal and the developer carrier or the space between the sheet metal and the sheet metal is filled with the developer, the capacitance between them increases, and as the developer decreases, the capacitance between the two increases. The rate at which air occupies the intervening space increases, and the capacitance decreases. Therefore, if the capacitance between the sheet metal and the developer carrier, or the relationship between the capacitance between the sheet metal and the developer amount is determined in advance, the developer amount level can be determined by measuring the capacitance. Can be detected.

[0011] The capacitance can be measured by measuring the current flowing through the other sheet metal when an AC bias is applied to the sheet metal as the developer carrier or the electrode. In other words, the developer remaining amount detecting means of this type detects the amount of the developer at the time of image formation in which a developing bias is applied to the developer carrier.

[0012]

However, as described above, even if the developer remaining amount detecting means capable of detecting the developer remaining amount level is provided, the developer remaining amount detected by the developer remaining amount detecting means is detected. In some cases, the value does not match the amount of the developer actually remaining in the developing device, that is, the remaining amount of the developer cannot be accurately detected. In particular, there is a possibility that an image defect, such as a so-called white spot, in which the entire image area cannot be visualized, may occur before a warning is issued.

For example, in the case of the above-described plate antenna type developer remaining amount detecting means, the capacitance between the developer carrier and the sheet metal as an electrode or the capacitance between the sheet metal as an electrode is respectively Even if there is no developer between them, the absolute value of the capacitance increases as the distance between them increases, and decreases as the distance between them increases.

As described above, a positional deviation due to an assembling tolerance of the developer remaining amount detecting means, a cartridge such as a tolerance of other parts of the cartridge or an electronic part of the image forming apparatus main body, or an individual of the image forming apparatus main body. The detected value may vary due to the difference.

Therefore, for example, in the case of a plate antenna type developer remaining amount detecting unit, when the developer remaining amount level is detected using only a relationship between a predetermined capacitance value and a developer amount, There may be a problem that the detection result is far from the amount of the developer actually remaining in the developing device.

In other words, when the capacitance detection value by the developer remaining amount detecting means when the developer is in the full state is larger than the initial set value (estimated value), it is larger than the actual developer remaining amount. There is a possibility that the estimation will be made and an image such as a white spot will be generated before the warning. Conversely, when the detected value of the capacitance when the developer is in the full state is smaller than the set value (ideal value), the estimated value is estimated to be smaller than the actual remaining amount of the developer, so that a large amount of There is a possibility that a warning indicating that there is no developer is issued even though the developer remains. If the user replaces the process cartridge in accordance with the warning, a large amount of toner is wasted, which leads to waste of resources.
The present invention has been made in view of such a problem.

Accordingly, an object of the present invention is generally to provide an image forming apparatus capable of accurately detecting the remaining amount of developer,
An object of the present invention is to provide a cartridge and an image forming system.

Another object of the present invention is to accurately detect the remaining amount of the developer in the developing device and notify the user of the remaining amount, so that a so-called blank image is generated before a warning is issued to the user. Image formation that can notify the user of an appropriate cartridge replacement time (purchase time), such that the amount of developer remaining at the time when the occurrence of a blank image is warned can be minimized. An apparatus, a cartridge, and an image forming system are provided.

Another object of the present invention is to provide an output of the developer remaining amount detecting means corresponding to each cartridge by using an output value in a state where there is no developer in at least a detection area of the developer remaining amount detecting means. Provided are an image forming apparatus, a cartridge, and an image forming system capable of always properly associating a value with the remaining amount of developer, detecting the remaining amount of developer accurately, and notifying the user of the detection. It is to be.

Another object of the present invention is to provide an image forming apparatus, a cartridge, and an image forming system which can reduce the cost by providing a storage means for storing information used for detecting the remaining amount of the developer in the image forming apparatus. It is to provide.

[0021]

The above object is achieved by an image forming apparatus, a cartridge and an image forming system according to the present invention. In summary, according to the first aspect of the present invention, there is provided an image in which a cartridge including a developer container, a developing unit, and a developer remaining amount detecting unit capable of sequentially outputting an output corresponding to the amount of the developer is detachable. In the forming apparatus, a developer sealing member that is opened at the start of use of the cartridge is provided between the developer accommodating container of the cartridge and the developing unit, and the developer sealing member is opened before the developer sealing member is opened. An image forming apparatus is provided, wherein information corresponding to a value output by the developer remaining amount detecting means in the apparatus main body is stored in a storage means provided in the apparatus main body.

According to one embodiment of the present invention, the value output by the developer remaining amount detection means in the apparatus main body before the developer sealing member stored in the storage means is opened. And the amount of developer in the cartridge is detected based on the information corresponding to (1) and the output of the developer remaining amount detecting means. In this case, based on a change amount of an output value of the developer remaining amount detecting unit from a value output by the developer remaining amount detecting unit in the apparatus main body before the developer sealing member is opened. The developer amount can be detected, and according to one embodiment, the developer amount is determined from a value output by the developer remaining amount detection unit in the apparatus main body before the developer sealing member is opened. The amount of developer can be detected using a table in which the amount of change in the output value of the remaining amount detecting means and at least the amount of developer are associated.

According to another embodiment of the first invention, the apparatus main body further stores information corresponding to an output value when the developer remaining amount detecting means detects a maximum amount of the developer. To memorize. In this case, information corresponding to a value output by the developer remaining amount detection unit in the apparatus main body before the developer sealing member stored in the storage unit is opened, and stored in the storage unit. Detecting the amount of developer in the cartridge based on information corresponding to an output value when the remaining amount of developer detects the maximum amount of developer and an output of the remaining amount of developer. Can be
According to one embodiment, the amount of developer remaining in the apparatus main body before the developer sealing member is opened is determined from the output value when the developer remaining amount detecting unit detects the maximum amount of developer. The absolute value of the value obtained by subtracting the value output by the detection means and the predetermined value is used as the developer use range, and the output value when the developer remaining amount detection means detects the maximum amount of the developer within the use range is used. The developer amount can be obtained from the relationship between the value multiplied by the correction value and the remaining amount of the developer.

According to another embodiment of the first aspect of the present invention, the developer sealing member is automatically opened at the start of use of the cartridge while the cartridge is mounted on the apparatus main body.

According to another embodiment of the first invention, the cartridge further holds cartridge identification information, and the apparatus main body further reads the cartridge identification information of the mounted cartridge, and stores the cartridge identification information. Has a means for storing the information.

The image according to any one of claims 2 to 10, wherein said apparatus main body further comprises means for outputting a signal for displaying any one of information on the detected amount of developer. Forming equipment.

According to another embodiment of the first aspect of the present invention, the apparatus main body further has a display means for transmitting a signal for displaying information on the detected amount of the developer to the display means. To display. According to another embodiment, the apparatus main body is further communicable with a device having a display means, and transmits a signal for displaying information on the detected amount of developer to the device having the display means.

According to the second aspect of the present invention, there is provided a developer storage container, a developing means, and a developer remaining amount detecting means capable of sequentially outputting an output corresponding to the amount of the developer. A possible cartridge, wherein a developer sealing member that is opened at the start of use of the cartridge is provided between the developer storage container and the developing unit, and the developer sealing member is opened before the developer sealing member is opened. A cartridge is provided, wherein information corresponding to a value output by the developer remaining amount detecting means in the apparatus main body is stored in a storage means provided in the image forming apparatus main body.

According to one embodiment of the present invention, the image forming apparatus main body is mounted in the image forming apparatus before the developer sealing member based on the information stored in the storage means is opened. The amount of developer in the cartridge is detected by correcting the result of calculation processing in which the output value of the remaining amount of developer and the output value of the remaining amount of developer are calculated and corrected by the correcting unit. .

According to another embodiment of the second aspect of the present invention, information corresponding to an output value when the developer remaining amount detecting means detects the maximum amount of the developer is stored in the image forming apparatus main body. Stored in the storage means provided. In this case, the image forming apparatus main body may include a value output by the developer remaining amount detecting unit in the image forming apparatus before the developer sealing member is opened based on the information stored in the storage unit. The output value of the developer remaining amount detecting means based on the information stored in the storage means when the developer remaining amount detecting means detects the maximum amount of the developer, and the output value of the developer remaining amount detecting means was calculated. The amount of the developer in the cartridge can be detected by correcting the result by the correction unit.

According to another embodiment of the second aspect of the present invention, the developer sealing member is automatically opened at the start of use of the cartridge while the cartridge is mounted on the image forming apparatus main body.

According to another embodiment of the second aspect of the present invention, the image forming apparatus main body holds cartridge identification information capable of identifying each cartridge when mounted on the image forming apparatus main body. Having means.

According to the third aspect of the present invention, there is provided an image forming system for forming an image on a recording medium using a cartridge which is detachably mountable to an image forming apparatus main body, wherein (a) a developer accommodating container, a developing means, A developer remaining amount detecting unit capable of sequentially outputting a signal corresponding to the amount of the developer, a developer sealing member that is opened at the start of use of the cartridge provided between the developer storage container and the developing unit, And (b) storage means for storing information corresponding to a value output by the developer remaining amount detection means in the apparatus main body before the developer sealing member is opened, A value output by the developer remaining amount detecting unit in the image forming apparatus before the developer sealing member is opened based on information stored in a storage unit, and an output value of the developer remaining amount detecting unit. Calculation The result, an image forming system characterized by and a control means for detecting the developer amount in the cartridge is provided by correcting by the correction means.

According to an embodiment of the third aspect of the present invention, the storage means further stores information corresponding to an output when the developer remaining amount detecting means detects the maximum amount of the remaining developer, The control unit controls the value output by the remaining developer amount detection unit in the image forming apparatus before the developer sealing member is opened based on the information stored in the storage unit, and stores the value in the storage unit. Correcting means for associating an output value obtained when the developer remaining amount detecting means detects the maximum amount of developer based on the stored information with an output value of the developer remaining amount detecting means. Then, the amount of the developer in the cartridge is detected by the correction.

According to another embodiment of the third invention, there is further provided a display means for displaying information on the detected amount of developer.

In one embodiment of the present invention, the developer remaining amount detecting means outputs a signal obtained by measuring a capacitance between at least two electrodes.

In each of the present invention, the cartridge comprises an electrophotographic photosensitive member, charging means for charging the electrophotographic photosensitive member, developing means for supplying a developer to the electrophotographic photosensitive member, and an electrophotographic photosensitive member. Has at least one of cleaning means for cleaning.

[0038]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image forming apparatus, a cartridge and an image forming system according to the present invention will be described in more detail with reference to the drawings.

Embodiment 1 An image forming system according to the present embodiment includes a laser beam printer (printer) 100 which is an electrophotographic image forming apparatus.
Image information is received from a host computer (not shown), and a recording medium such as a recording paper, an OHP sheet, or a cloth is formed by an electrophotographic image forming process using a process cartridge B detachably mounted on the image forming apparatus main body A. And the like to form an image.

First, a printer 100 to which a process cartridge B constructed according to the present invention can be mounted will be described with reference to FIGS. The printer 100
It has a drum-shaped electrophotographic photosensitive member, that is, a photosensitive drum 1. The photosensitive drum 1 is charged by a charging roller 2 serving as a charging unit, and then is subjected to scanning exposure with laser light L corresponding to image information emitted from a laser scanner 3, and the photosensitive drum 1 is charged according to image information. Latent image is formed. This latent image is developed by the developing device C by the developing unit 5 to be a visible image, that is, a toner image.

That is, the developing device C has a developing chamber 5A provided with a conductive developing roller 5a as a developer carrying member, and a developer accommodating container 4 formed adjacent to the developing chamber 5A. Then, the developer T in the developer container 4 moves to the developing chamber 5A and is supplied to the developing roller 5a. A stirring means 8 which rotates in the direction of the arrow in FIG. 1 is provided in the developer accommodating container 4, and the developer T is loosened by the rotation of the stirring means 8, and supplied to the developing roller 5a. Is done. In this embodiment, as the developer T, an insulating magnetic one-component toner was used. The developing roller 5a has a built-in fixed magnet 5b, and the developer is conveyed by rotating the developing roller 5a, and a triboelectric charge is applied by a developing blade 5c which is a developer layer thickness regulating member. At the same time, a developer layer having a predetermined thickness is formed and supplied to the developing area of the photosensitive drum 1. The developer supplied to the developing area is transferred to a latent image on the photosensitive drum 1 to form a toner image. The developing roller 5a is connected to a developing bias applying unit 33 (FIG. 3), and is usually applied with a developing bias voltage in which a DC voltage is superimposed on an AC voltage.

On the other hand, the recording medium P set in the sheet cassette D in synchronization with the formation of the toner image
2. The sheet is conveyed to the transfer position via the conveying means 13a. A transfer roller 14 as a transfer unit is disposed at the transfer position, and transfers a toner image on the photosensitive drum 1 to the recording medium P by applying a voltage.

The recording medium P to which the toner image has been transferred is conveyed to the fixing means 15 by the conveying means 13b. Fixing means 1
Reference numeral 5 denotes a fixing roller 15b including a heater 15a and a driving roller 15c, and applies heat and pressure to the recording medium P passing therethrough to fix the transferred toner image on the recording medium P.

The recording medium P is discharged to the discharge tray 16 by the transport means 13c. The discharge tray 16 is provided on the upper surface of the apparatus main body A of the printer 100.

After the transfer of the toner image onto the recording medium P by the transfer roller 14, the cleaning device 7 removes the developer remaining on the photoreceptor drum 1, and is then subjected to the next image forming process. Is done. The cleaning device 7 scrapes off the residual developer on the photosensitive drum 1 and collects it in a waste developer container 7b by an elastic cleaning blade 7a as cleaning means provided in contact with the photosensitive drum 1.

In this embodiment, as shown in FIG. 2, the process cartridge B has a stirring means inside and a developer frame 9 for forming the developer accommodating container 4 for accommodating the developer.
And a developing frame 10 forming a developing chamber 5A for holding a developing means 5 such as a developing roller 5a and a developing blade 5c are welded together to form a developing device (developing unit) C as an integral unit. The photosensitive drum 1, the cleaning device 7 including the cleaning blade 7a and the waste developer container 7b, and the cleaning frame 11 to which the charging roller 2 is attached are integrally combined to form a cartridge. The process cartridge B is detachably mounted on a cartridge mounting means 50 (FIG. 1) provided on the image forming apparatus main body A by a user.

A developer sealing member 6 is provided between the developer container 4 and the developing chamber 5A. The developer sealing member 6 is not opened until the process cartridge B is used, and is automatically opened when the process cartridge B is mounted on the image forming apparatus main body A, as described later in detail.

The printer 100 of this embodiment has a developing device C
A developer amount detecting device provided with a developer remaining amount detecting means 30 capable of sequentially detecting the remaining amount according to the consumption of the developer T in the inside.

In this embodiment, a plate antenna system is used as the developer remaining amount detecting means 30. As shown in FIG. 2, a first sheet metal 31 and a second sheet metal 32 are provided as a plate antenna over substantially the entire area in the longitudinal direction in the developing device C. The second sheet metal 32 is provided at a position facing the developing roller 5a, substantially in parallel with its longitudinal direction. This second
The first sheet metal 3 faces the sheet metal 32 and is substantially parallel to the longitudinal direction thereof.
1 is provided.

As described above, the first sheet metal 31 and the second sheet metal 32
Are arranged in the developing device C, and the developing roller 5a and the second sheet metal 32 which change with the decrease of the developer T in the developing device C are changed.
By observing the capacitance between the first sheet metal 31 and the second sheet metal 32, the developer amount in the developing device C can be known at any time.

The first sheet metal 31 and the second sheet metal 32 as the plate antenna can be basically used without any particular limitation as long as they are materials through which a current can flow. We use SUS which resists rust. In the present embodiment, the first sheet metal 31 and the second sheet metal 32 are provided on the developing frame 10 forming the developing chamber 5A.

Referring to FIG. 3, the circuit configuration of the developer amount detecting apparatus will be described. In this embodiment, the developing roller 5a and the first sheet metal 31 are provided with the process cartridge B mounted on the image forming apparatus main body A. In this state, it is electrically connected to a developing bias circuit 33 which is a developing bias applying unit provided as a voltage applying unit provided in the image forming apparatus main body A. Then, an AC bias of about 2 KHz, which is a normal developing bias, and a DC bias of about −400 V are applied to the developing roller 5 a.
And the first sheet metal 31.

When a predetermined AC bias is output from the developing bias circuit 33, the applied bias is applied to the reference capacitor 34, the developing roller 5a, and the first metal plate 31.
Respectively. As a result, a voltage V1 is generated at both ends of the reference capacitor 34, the capacitance C2 between the developing roller 5a and the second metal plate 32, and the capacitance of the first metal plate 31 and the second metal plate 32 are applied to the second metal plate. Capacitance C between
A current corresponding to 3 is generated. This current value is converted into a voltage V2 by calculation. The capacitance C4 is equal to the value of the developing roller 5a.
This is a combined capacitance of the capacitance C2 between the first metal plate 31 and the second metal plate 32 and the capacitance C3 between the first metal plate 31 and the second metal plate 32.

In the main body side developer remaining amount detection section 25, the detection circuit 35
A voltage V3 is generated from a voltage difference between a voltage V1 generated at both ends of the voltage V4 and a voltage V2 between the sheet metal pair, and is output to the AD conversion unit. The AD converter 36 outputs the result of digital conversion of the analog voltage V3 to the main body controller 21.

Hereinafter, the developer remaining amount detecting means 30 detects the electrostatic capacity (C2) between the developing roller 5a and the second metal plate 32 and the electrostatic capacity between the first metal plate 31 and the second metal plate 32. (C
According to 3), a signal sequentially output via the second sheet metal 32 is simply referred to as “output (detection value) of the developer remaining amount detecting means” or the like. Based on this, the voltage value detected by the main body control unit 21 is simply referred to as “detected voltage value V3”.

The main body control section 21 uses the detected voltage value V3 converted into the digital value to calculate the operation section 23, the control means 22, and the developer remaining amount correction table (developer amount correction table) shown in FIG. Using the remaining amount correction table storage unit) 24, the developer remaining amount level is determined. In this embodiment,
The main body control section 21 obtains the remaining percentage of the developer based on the detected remaining amount of the developer, and displays the display means 26 provided in the apparatus main body A.
Then, the user is informed of the information or the fact that the developer has decreased to such an extent that a predetermined quality image cannot be formed, for example, a warning of "no developer" is displayed.

Next, the principle of detecting the amount of the developer using the developer remaining amount detecting means 30 will be described.

FIG. 5 shows a state between the developing roller 5 a as the developer remaining amount detecting means 30 and the second sheet metal 32 and the first sheet metal 3.
The capacitance value C measured between each of the first and second sheet metals 32
2, a detection voltage value V3 corresponding to the sum of C3;
The relationship between the developer remaining amount in the developing device C is shown. In FIG. 5, the vertical axis indicates the detected voltage value V3, and the horizontal axis indicates the remaining amount of the developer (g). Here, in the present embodiment, from the relationship of the conversion circuit, the developing roller 5a and the second sheet metal 32 are expressed as (capacitance, detection voltage) = (13 pF, 1.0 V), (18 pF, 0.8 V). And the total capacitance between the first sheet metal 31 and the second sheet metal 32 and the decrease / increase relationship between the detected voltage value V3 are opposite to each other. The detection voltage is set to be small when the capacitance is large, and to be large when the capacitance is small.

Therefore, in a state where there is no developer in the developing chamber 5A, that is, in a state where there is no developer between the developing roller 5a and the second sheet metal 32 and between the first sheet metal 31 and the second sheet metal, The detected capacitance value shows the minimum value,
The detection voltage value V3 indicates the maximum value. The maximum value of the voltage detected by the developer amount detection device is called "PAE value: (plate antenna empty value)".

In this embodiment, the developer remaining amount detecting means 3
As 0, the developing roller 5a and the first and second sheet metals 31, 32 relatively close to the developing roller 5a are used. For this reason, due to the arrangement of the developer remaining amount detecting means 30, as shown in FIG. 5, after the developer in the developing and developing device C is consumed by approximately half or less, the detection voltage value V3 increases (the capacitance of the electrostatic capacitance is reduced). Decrease)
Starts, and thereafter, a decrease in the remaining amount of the developer until the developer runs out can be sequentially detected. However, the present invention is not limited to this.
The plate antennas of the first and second embodiments
An input-side electrode and an output-side electrode, which are made of a sheet metal similar to a sheet metal, are provided at arbitrary positions in the developing device, and by measuring the capacitance between the two electrodes, the remaining amount of the developer is eliminated from a point in time when the remaining amount is larger It is of course possible to adopt a configuration in which the range up to can be detected sequentially.

Here, as described above, the developer remaining amount detecting means 30 of the plate antenna type uses the developing roller 5a.
The capacitance between the sheet metal as the electrode and the capacitance between the sheet metal as the electrode depends on the respective positional relationships, and the detection voltage value is obtained even when there is no developer due to the individual difference of the process cartridge B. May vary. Also, the detected voltage value varies due to a deviation in the positional relationship of the plate antenna due to a manufacturing lot of the developer to be housed, a use environment, other parts of the cartridge, an assembly tolerance, etc., and a tolerance of electronic parts of the image forming apparatus main body A. Occurs.

More specifically, as shown in FIG. 5, an ideal value (− ● −) and an actual measured value PA are determined as differences between individual cartridges, for example, due to the positional relationship of the plate antenna.
(-□-) and the PAE value may be different. In the example shown in FIG. 5, where the ideal value of the PAE value is 3.0 V, the measured value PA is 2.8 V.

On the other hand, as shown in FIG. 5, a difference between the ideal curve and the actually measured value of the voltage value detected by the developer amount detecting device usually occurs due to the individual difference between the process cartridge B and the image forming apparatus main body A. However, the curved shape does not change if the amount of the developer accommodated in the developing device C is the same. Therefore, the PAE is caused by the displacement due to various causes as described above.
Since the values are different, the curve indicating the relationship between the detected voltage value and the remaining amount of the developer is relatively shifted between the ideal curve and the actually measured value PA as shown in FIG.

The ideal value (-●-) shown in FIG.
Table 1 shows data on the remaining amount of the developer and the detected voltage in A (-□-).

[0065]

[Table 1]

As described above, since the detection voltage V3 is shifted due to the individual difference between the process cartridge B or the image forming apparatus main body A due to the above-described cause, a predetermined capacitance detection value (detection voltage value V3) When the developer remaining level is detected based only on the relationship between the amount of developer and the amount of developer,
In some cases, a problem may occur in which the amount of the developer remaining in the developing device C is substantially different from the detection result.

For example, as shown in FIG. 5, the PAE value of the actually measured value PA is smaller than the ideal value (3.0 V) (2.8).
V) In the case of having the output characteristic, the developer remaining amount is estimated to be larger than the actual amount. Therefore, for example, when the remaining amount of the developer is 20
At the time point g, the entire area of the image cannot be visualized and an image defect occurs, that is, there is a risk of so-called white spots.
When it is set to give a warning of "no developer" when the voltage becomes 2.2 V smaller than V, the actually measured value PA indicates that a blank image has a detection voltage value of 2.0 V (2.8 V).
(PAE value) −0.8 = 2.0V), but no warning is displayed until the detected voltage value reaches 2.2V. Therefore, there is a case where a blank image is output before a warning is issued to the user. As a result, there may be user complaints.

On the other hand, when the actually measured PAE value has an output characteristic larger than the ideal value, on the contrary,
When the remaining amount of the developer is determined from the relationship between the remaining amount of the developer indicated by the ideal curve and the detected voltage value, the remaining amount of the developer is estimated to be smaller than the actual amount. For this reason, at the warning point of “no developer” which is set according to the ideal curve and where a blank image may occur, the developing device C is actually
There is still a lot of developer left inside, and the developer is wasted.

Therefore, in this embodiment, (1) the storage means 20 is provided in the image forming apparatus main body A, and the amount of developer detected in the image forming apparatus main body A before the developer sealing member 6 is opened. The voltage detected by the detection device, that is,
The PAE value is written in the storage means 20. (2) Using the PAE value stored in the storage unit 20, the remaining amount of the developer is obtained by using the remaining amount of developer correction table in accordance with the amount of change in the detected voltage value V3 from the PAE value. (3) The result is displayed on the display means 26 as needed. Is performed. As a result, PAE is caused by individual differences between the process cartridge B or the image forming apparatus main body A.
Even when the values are different, this can be corrected, and the difference between individual cartridges can be absorbed to more accurately detect the remaining amount of the developer one by one.

The storage means 20 provided in the image forming apparatus main body A and the control configuration of the storage means 20 will be described. In this embodiment, the image forming apparatus main body A has a readable / writable memory 20 as the storage means 20. The main body control unit 21 controls reading and writing of information from and to the memory 20.

As the storage means 20 used in the present invention, an ordinary semiconductor electronic memory such as a combination of a nonvolatile memory, a volatile memory and a backup battery can be used without any particular limitation.

As for the capacity of the memory 20, it is assumed that the memory 20 has a capacity enough to store a plurality of pieces of information such as the cartridge usage amount and the cartridge characteristic value. Further, the memory 20 can write and store the used amount of the cartridge as needed.

As shown in FIG. 4, the main body control unit 21 includes a control unit 22, an arithmetic unit 23, a developer remaining amount correction table (developer remaining amount correction table storage unit) 24, and a main body side developer remaining amount detection unit. It has a part 25 and the like.

Then, as described above, the signal from the developer remaining amount detecting means 30 is sent to the main body control section 21 of the image forming apparatus main body A. The output signal from the developer remaining amount detecting means 30 is converted into a voltage signal by the main body side developer amount detecting unit 25, and the arithmetic unit 23 uses the voltage signal and information stored in the memory 20 to perform a predetermined Is performed. In addition, the control unit 22 checks the data obtained by the calculation unit 23 using the developer remaining amount correction table 24 to appropriately correct the developer remaining amount detection value and determine the developer remaining amount level. I do. Further, the main body control section 21 obtains the remaining amount of the developer (%) based on the detected remaining amount of the developer, and displays the information or a warning of “no developer” on the display means 26 of the apparatus main body A. The signal to be output is output.

Various information can be stored in the memory. In this embodiment, it is assumed that at least the PAE value information and the detected developer remaining amount Y (%) information are stored. .

The information stored in the memory 20 is always in a state where it can be transmitted / received to / from the arithmetic unit 23 in the main body control unit 21. The information is calculated based on the information and the control unit 22 checks the data. Is being done.

According to the present embodiment, the PAE value is determined by the developer remaining amount detecting means 30 before the developer sealing member 6 is opened with the process cartridge B mounted in the image forming apparatus main body A. And is written to the memory 20. That is, the plate antenna (the first sheet metal 31 and the second sheet metal 32) as the developer remaining amount detecting means 30 and the developing roller 5a are provided in the developing chamber 5A, and the developer sealing member 6 is opened. Until then, there is no developer between the developing roller 5a and the second sheet metal 32 and between the first sheet metal 31 and the second sheet metal 32. Therefore, before the developer sealing member 6 is opened, the voltage value detected by the developer remaining amount detecting means 30 indicates the maximum value, that is, the PAE value. In the process cartridge B of this embodiment, the PAE value is about 3.0 V
It is.

The main body control section 21 stores a PA of the detected voltage value V3 as a table for correcting the detected voltage value.
The relationship between the amount of change (V) from the E value and the remaining amount of developer (g) in the developing device C is stored in the developer remaining amount correction table (developer remaining amount correction table storage unit) 24 in advance. . In this embodiment, the difference (V) between the PAE value and the detected voltage value is made to correspond to the remaining amount of the developer as the amount of change of the detected voltage value V3 from the PAE value. Table 2 shows the developer remaining amount correction table 24 used in this embodiment.

[0079]

[Table 2]

As shown in Table 2, in this embodiment, it is assumed that a blank image may occur when the remaining amount of the developer in the developing device C becomes 20 g or less. The change amount of the detection voltage V3 from the PAE value is 0.8 V
In the following cases, the display means 26 of the apparatus main assembly A is set so as to display a warning of "no developer". or,
In the present embodiment, the variation (V) from the PAE value is set to 0.8 to
It is divided into appropriate step widths between 2.0 V and is made to correspond to the remaining amount (g) of the developer. Further, the remaining amount (g) of the developer and the remaining amount (%) of the developer for indicating what percentage of the usable developer remains when not used are associated with each other.

Further, in this embodiment, when the amount of the developer charged when the process cartridge B is not used is 200 g, and when the remaining amount of the developer in the developing device C becomes 20 g or less, there is a possibility of white spots. The amount of developer that can be actually used is 180
g, which indicates what percentage of the developer remains with respect to this usable amount of developer. In the present embodiment, the amount of the remaining developer is 50 g,
From about (amount of usable developer 30 g), an increase in the voltage detected by the developer amount detection device (a decrease in capacitance) starts. Therefore, the remaining developer amount (%) before that can be displayed as “30% or more” or “100%”.

Here, the mechanism for storing the PAE value in the memory 20 will be described. As described above, in the present embodiment, the developer remaining before the developer sealing member 6 is opened in the image forming apparatus main assembly A is removed. The detected voltage value detected by using the amount detecting means 30 is defined as a PAE value.

As shown in FIG. 1, a developer sealing member 6 is provided between the developer container 4 of the process cartridge B and the developing chamber 5A. The sealing member is not opened until the process cartridge B is used, and is automatically opened when the process cartridge B is mounted on the image forming apparatus main body A.

The developer sealing member 6 may have a structure that can be mechanically tilted by a cam or the like, or may be a rollable seal member. In this embodiment, a rollable seal member is used as the developer sealing member 6.

FIG. 6 shows a cross section of the developer sealing member 6 and the automatic opening means 17 viewed from the side of the developing chamber 5A. FIG. 6 does not show the developing roller 5a and the developing blade 5c. In this embodiment, the automatic opening means 17 of the developer sealing member 6 is attached to the process cartridge B,
When the sealing detection unit 18 of the automatic opening means 17 receives the opening signal from the automatic opening means 17, the developer sealing member (seal member) 6 is wound up in the direction shown by the arrow in the figure to perform automatic opening. I have.

When storing the PAE value information in the memory 20, first, the main body control section 21 checks whether or not the process cartridge B is mounted in the main body A of the image forming apparatus. Is the sealing detector 1
It is confirmed whether or not an opening signal of the developer sealing member 6 is input to 8. Here, when it is determined that the opening has not been performed, the main body control unit 21 measures the detection voltage V3 by the developer remaining amount detection unit 30 and stores the value in the memory 20 as the PAE value.

Thereafter, the main body control section 21 sends an opening signal to the sealing detecting section 18, and the developer sealing member 6 is automatically opened.
The developer enters the developing chamber 5A from the developer storage container 4.

Referring to the flowchart (step (S) 101 to step (S) 110) shown in FIG.
AE value storage operation in memory 20 and developer sealing member 6
Will be further described. S101: The power of the image forming apparatus main body A is turned on. S102: The main body control unit 21 checks whether the process cartridge B is mounted in the main body A of the image forming apparatus. If “No” is determined, the process proceeds to S103,
The display means 26 displays "no cartridge". “Y
If it is determined to be "es", the process proceeds to S104. S104: The main body control unit 21
Check that the has been opened. If "Yes" is determined, the process proceeds to S105, where the PAE value is confirmed, and the sequence ends (S106). If “No” is determined, the process proceeds to S107. S107: The detection voltage V is detected by the developer remaining amount detection means 30.
Measure 3. S108: The detection voltage V3 measured in S107 is
It is stored in the memory 20 as an AE value. S109: The main body control section 21 sends an opening signal to the sealing detection section 18, and the sealing member 6 is automatically opened. S110: End the sequence.

Next, the operation of detecting the remaining amount of the developer will be described with reference to the flowchart (step (S) 201 to step (S) 210) of FIG. The developer remaining amount correction table 24 used halfway is shown in Table 2. S201: The power of the image forming apparatus main body A is turned on. S202: The main body side developer remaining amount detection unit 25
Check whether the PAE value is stored in the memory. Here, when it is determined as “No”, the process proceeds to S203,
Information indicating that the process cartridge B has an abnormality is displayed on the display unit 26 of the image forming apparatus main body A.
If "Yes" is determined, the process proceeds to S204. S204: The main body side developer remaining amount detection unit 25 measures the detected voltage value V3. S205: The computing unit 23 calculates the amount of change (V) of the detected voltage value V3 from the PAE value from the relationship between the PAE value and the detected voltage value V3. S206: The control unit 22 compares the value calculated by the calculation unit 23 in S205 with the developer remaining amount correction table 24. S207: The control unit 22 transmits a signal indicating that the remaining amount of the developer is Y% to the display unit 26 of the image forming apparatus main body A, and displays the information on the display unit 26. S208: The control means 22 determines that the remaining amount of developer Y is
The (%) value information is written to the memory 20 and updated. S209: The control unit 22 determines that the remaining amount of developer Y (%) is 0%
It is checked whether or not it has reached, and if it is determined as “No”, S
Returning to 204, the above chart is repeated. Also, "Ye
If it is determined to be s ", the process proceeds to S210. S210: The sequence ends.

The control according to the above-described flowchart is performed to evaluate the display of the remaining amount of the developer accompanying the consumption of the developer for the process cartridges B (PA-a, PA-b) having the developer amount detecting devices having different PAE values. Then, Figure 9
As shown in (1), the residual amount of the developer amount can be sequentially detected by absorbing the individual difference of the process cartridge B. The vertical axis in FIG. 9 indicates the measured value V3 of the detection voltage by the developer amount detection device.
, And the horizontal axis indicates the remaining amount display Y (%) of the developer in the developing device C.

The process cartridge B of this embodiment can have cartridge identification information (cartridge ID information) for identifying each process cartridge. This is to notify the image forming apparatus main body A that the process cartridge B is different from the previously used process cartridge B when the process cartridge B is replaced. As means for holding the cartridge ID information, a magnetic film or the like may be attached to the side of the cartridge, or may be distinguished by a bar code or the like.
In this case, cartridge ID information unique to the cartridge,
For example, if the serial number is known, the method is not particularly limited.

In this embodiment, a bar code seal is provided on the process cartridge B as cartridge identification information holding means (not shown), and cartridge identification information reading means (not shown) is provided on the image forming apparatus main body A. A barcode recognition unit is provided. That is, a bar code indicating unique ID information is attached to each process cartridge B in the process of manufacturing the process cartridge B, and the bar code recognition unit reads the bar code when the image forming apparatus main body is mounted, and the image forming apparatus main body A It is stored in the memory 20. The barcode recognition section recognizes infrared light by irradiating the barcode.

The cartridge ID information is recognized on the image forming apparatus main body A side and stored in the memory 20 of the image forming apparatus main body A. Further, in association with the cartridge ID information, information relating to the detection of the remaining amount of the developer by the developer amount detecting device, such as the PAE value, is stored in the memory 2 of the image forming apparatus main body A.
0 is stored.

Thus, even when the process cartridge B in use is removed from the image forming apparatus main body A and is replaced, when the process cartridge is used again, the image forming apparatus main body A has the cartridge ID.
By reading the information (PAE value) stored in the memory 20 of the image forming apparatus main body A corresponding to the cartridge ID, the remaining amount of the developer and the capacitance corresponding to each cartridge are recognized. The relationship between (detection voltage) can be corrected, and the remaining amount of the developer can always be accurately detected.

As described above, according to the present invention, the capacitance detected by the developer remaining amount detecting means 30 in a state where there is no developer depends on the positional relationship of the developer remaining amount detecting means 30 and the like. Therefore, the relationship between the remaining amount of the developer and the detected capacitance value (detected voltage value) can be corrected, and the remaining amount of the developer can be accurately detected. or,
By displaying the information on the detected remaining amount of the developer, the user can be notified of the exact cartridge replacement time (purchase time).

Further, according to the present invention, the image forming apparatus main body A
A memory 20 is provided in each of the cartridges, and information necessary for the sequential detection of the remaining amount of the developer is stored therein and used, whereby a storage means is provided in each cartridge, and information necessary for the detection of the remaining amount of the developer is stored therein. The cost can be reduced as compared with the case of causing the cost.

In the present embodiment, the developer remaining amount is calculated using the developer remaining amount correction table, but the detected voltage value is corrected using a predetermined weighting function using the PAE value. It is good.

Embodiment 2 Next, another embodiment of the present invention will be described. In this embodiment, the configurations of the image forming apparatus and the process cartridge are basically the same as those of the first embodiment.
Is different in the control of the developer remaining amount detection. Therefore, components having the same configuration and function are denoted by the same reference numerals, detailed description thereof will be omitted, and only the features of this embodiment will be described.

In the present embodiment, the circuit configuration of the developer amount detecting device, the relationship between the decrease and increase of the detection voltage and the capacitance by the developer amount detecting device, and the mechanism for detecting the remaining amount of the developer are the same as those in the first embodiment. It is.

In the first embodiment, the measurement was performed using the developer remaining amount detecting means 30 before the developer sealing member 6 was opened in a state where the process cartridge B was mounted on the image forming apparatus main body A. The relationship between the voltage detected by the developer amount detection device and the remaining amount of the developer was corrected using the PAE value.

In this embodiment, furthermore, information on a detected voltage value (hereinafter, referred to as a PAF value: “plate antenna full value”) in a state in which the developer in the developing chamber 5A is fully filled is also included. Use. Then, as described later in detail, the PAE value and the PAF value stored in the storage means (memory) 20 in advance.
The remaining amount of the developer is obtained using a weighting function using the relationship between the value and the remaining amount of the developer.

That is, in a state where there is no developer in the developing chamber 5A, that is, in a state where there is no developer between the developing roller 5a and the second sheet metal 32 and between the first sheet metal and the second sheet metal, The capacitance detected by the amount detecting means 30 indicates a minimum value, and at this time, the detection voltage V3 indicates a maximum value (PAE value).
On the other hand, when the developer is maximally filled in the developing chamber 5A, that is, between the developing roller 5a and the second metal plate 32, and between the first metal plate 31 and the second metal plate 32, the developer is maximally charged. In some cases, the capacitance detected by the developer remaining amount detecting means 30 indicates a maximum value, and at this time, the output voltage V3 indicates a minimum value (PAF value).

As described in the first embodiment, the developer remaining amount detecting means 30 of the plate antenna type is
The capacitance between a and the second metal plate 32 as an electrode, or the capacitance between the metal plates 31 and 32 as electrodes is influenced by the respective positional relationships, and is detected by the developer amount detecting device depending on the individual cartridge. The voltage value varies. In addition, such variations may be caused by the production lot of the developer,
It also arises from the use environment, other tolerances of the parts of the cartridge, misalignment of the positional relationship of the plate antenna, and electronic parts of the image forming apparatus main body A. Therefore, PAE value, PAF
The values vary.

Since the deviation is caused by the individual difference of the process cartridge B or the image forming apparatus due to various causes, the developer remaining amount level is determined based only on the relationship between the preset detection voltage value and the remaining amount of the developer. When the detection of
There is a problem that the amount of the developer actually remaining in the developing device C is substantially different from the detection result. For example, before warning the user that there is a risk of white spots due to deviation of the PAE value and the PAF value from the ideal values due to individual differences between the process cartridge B and the image forming apparatus main body A, and that there is no developer. In some cases, a defective image such as a blank image may be generated, or a situation may occur in which a large amount of usable developer still remains at the time of issuing the "no developer" warning. This can cause user complaints.

Therefore, in the present embodiment, (1) the storage means (memory) 20 is provided in the image forming apparatus main body A, and the image is detected in the image forming apparatus main body A before the developer sealing member 6 is opened. The detected voltage value, that is, the PAE value is written in the storage means 20. (2) The minimum value of the detected voltage value (the maximum value of the capacitance value), that is, the PAF value, is written in the storage unit 20 of the image forming apparatus main body A. The comparing means compares the detected voltage value which is constantly detected with the previously written PAF value, and rewrites the PAF value in the storage means 20 when the detected voltage value is smaller than the previously written PAF value. repeat. (3) A weighting function using the relationship between the PAE value, the PAF value, and the remaining amount of the developer is stored in the main body control unit 21 of the image forming apparatus main body A or the storage unit 20 in advance. Then, the correction value (Z) of the weighting function, which is set in advance at a predetermined interval, is sequentially substituted into the predetermined relationship between the weighting function and the detected voltage value, and the correction value (Z) satisfying the predetermined relationship is determined. I do. (4) The remaining amount of the developer is obtained by using the remaining amount of developer correction table 24 in which the correction value (Z) is associated with the remaining amount of the developer. (5) The result is displayed on the display means 26 as needed. Is performed. As a result, the PAE is caused by the individual difference between the process cartridge B or the image forming apparatus main body A.
This is corrected even when the values and PAF values are different,
By absorbing individual differences, the remaining amount of the developer can be sequentially detected more accurately.

The storage means 20 provided in the image forming apparatus main body A and the control configuration of the storage means 20 will be described. In this embodiment, the storage means 20 is the same as the readable / writable memory 20 of the first embodiment. Can be used.
The main body control unit 21 of the image forming apparatus main body A controls reading and writing of information from and to the memory 20.

As shown in FIG. 10, the main body control section 21
The control unit 22 includes a calculation unit 23, a remaining developer amount correction table (developer remaining amount correction table storage unit) 24, a main body side developer remaining amount detection unit 25, and an operation expression (operation expression storage unit) 27. I have.

The signal from the developer remaining amount detecting means 30 is sent to the main body control section 21 of the image forming apparatus main body A.
The output signal from the developer remaining amount detecting means 30 is converted into a voltage signal by the main body side developer remaining amount detecting unit 25, and the arithmetic unit 23 converts the voltage signal, the arithmetic expression 27 and the information stored in the memory 20 into a voltage signal. Based on this, predetermined arithmetic processing described later is performed. In addition, the control unit 22 checks the data obtained by the calculation unit 23 using the developer remaining amount correction table 24 to appropriately correct the developer remaining amount detection value and determine the developer remaining amount level. I do. Further, the main body control section 21 obtains the remaining amount of the developer (%) based on the detected remaining amount of the developer, and displays the information or a warning of “no developer” on the display means 26 of the apparatus main body A. Let it.

As the memory 20, the same one as in the first embodiment can be used. Various information can be stored in the memory 20. In this embodiment, at least the PAE value information, the PAF value information, the W value information described later, and the developer remaining amount Y (%) value information are stored in the memory 20. Stored and stored.

The information stored in the memory 20 is always in a state where it can be transmitted / received to / from the arithmetic unit 23 in the main body control unit 21. The information is calculated based on the information and the control unit 22 checks the data. Is being done.

According to the present embodiment, the PAE value is determined by using the developer remaining amount detecting means 30 before the developer sealing member is opened in a state where the process cartridge B is mounted in the image forming apparatus main body A. Is detected and written to the memory 20. The mechanism for storing the PAE value in the memory 20 is the same as in the first embodiment, and is performed according to the flowchart of FIG. In this embodiment, the PAE value is about 3.0V.

On the other hand, the PAF value is determined in a state where the process cartridge B is mounted in the main assembly A of the image forming apparatus, the developer sealing member 6 is opened, and the filling of the developing chamber 5A with the developer is completed. Is measured using the developer remaining amount detecting means 30 and written into the memory 20. And the printer 10
If the detected voltage value by the developer amount detection device indicates the minimum value (the capacitance is the maximum value) while 0 is operating, it is updated as needed. In this embodiment, the PAF value is approximately 1.0V.

In this embodiment, the developer remaining amount correction table 24 for correcting the detection voltage value includes a correction value Z of an arithmetic expression (weighting function) based on the detection voltage value V3, the PAE value, and the PAF value. , And the amount of developer (g) are stored in the main body controller 21 in advance. Table 3 shows the developer remaining amount correction table 24 used in this embodiment.

[0114]

[Table 3]

In the control method of the present embodiment, [PAW value-PAF value] = [PAE value-W-PAF value] (1) was set as the use range of the developer.

That is, the usage range of the developer is the detection voltage value corresponding to the amount of the developer at the time when the warning of “no developer” is issued on the assumption that a blank image is likely to occur, that is, the blank voltage ( PAW value) and the PAF value.

Here, this PAW value (white spot voltage) has a relationship such as PAW value = [(PAE value) − (experimental value W based on accumulation of experimental data)] (2) ing. White spot voltage (PAW value)
Means that the detected voltage value at the time when the blank image occurs is PA
It is represented by how small the value is below the E value.
That is, W (V) is, for example, the difference between the detected voltage value and the PAE value at the time when the remaining amount of the developer is reduced to 20 g, which is a warning point of a blank image in the first embodiment. It is an experience value based on statistical data accumulation. In the developer remaining amount detecting means 30 of this embodiment, W is 0.8 (V) (FIG. 5), and the usage range of the developer is [PAW value-PAF value] = [PAE value-W-PAF]. value]
= 3.0-0.8-1.0 = 1.2 (V).

The weighting function is expressed as follows: F (PAF, PAE, W) = | PAF value + [PAW value−PAF value] × Z | (3)

In the weighting function represented by the above equation (3), the coefficient Z is a correction value of the weighting function. this is,
This is a value set so as to divide the range of use of the developer at appropriate intervals, and is stored in the main body control unit 21 in advance as a developer remaining amount correction table 24.

The main body control section 21 calculates the following equation (4) showing the relationship between the weighting function F (PAF, PAE, W) shown in equation (3) and the detected voltage value V3: | PAF + [PAW −PAF] × Z | ≦ | V3 | (4) is stored as the arithmetic expression 27, and the remaining amount of the developer is determined by sequentially substituting the coefficient Z into the relationship of the expression (4). .

That is, when detecting the remaining amount of the developer, for example, in the developer remaining amount correction table 24 shown in Table 3, Z = 0.1 corresponding to the section having the largest amount of the developer is substituted into the equation (4). I do. If this does not hold, the remaining amount of developer is 1
And the remaining amount of the developer is 1
If it is 00%, it is displayed on the display means 26. Also, when Z = 0.
When the above expression (4) is satisfied by substituting 1, the developer amount is determined to be less than 100 (g), and the developer remaining amount correction table in Table 3 is used to determine the next smaller amount of developer. Is substituted into the equation (4). If this is not established, it is determined that the remaining amount of the developer is 50 g, and for example, the display means 26 displays that the remaining amount of the developer is 30%. That is, in this case, the above equation (4)
Then, the correction value Z of the weighting function corresponding to the remaining amount of the developer in advance is sequentially substituted from the one corresponding to the section having the larger remaining amount of the developer, and when the equation (4) is established, the Z value is sequentially substituted. By repeating the calculation based on the expression (4), Z that does not satisfy the expression (4) is determined, and the remaining amount of the developer is recognized.

As shown in Table 3, in this embodiment, when the remaining amount of the developer in the developing device C becomes 20 g or less, there is a possibility that a blank image may be generated. When Z) becomes 0.99 or less, the display means 26 of the apparatus main assembly A is set so as to display a warning indicating "no developer". In addition, the correction value (Z) is set to an appropriate step width between 0.1 and 0.99, and is made to correspond to the remaining amount of the developer.
Further, the remaining amount of developer (g), the remaining amount of developer (g), and the remaining amount of developer (%) for indicating what percentage of available developer remains when not used are corresponded. ing.

In this embodiment, when the process cartridge B is not used, the amount of the developer charged is 200 g, and when the remaining amount of the developer in the developing device C becomes 20 g or less, there is a possibility that the process cartridge B may slip out. Therefore, the amount of developer that can be actually used is 180 g, and the percentage of the remaining developer with respect to the amount of usable developer is displayed. Further, in this embodiment, due to the arrangement relationship of the developer remaining amount detecting means 30, the detection voltage value by the developer amount detecting device is increased from the developer remaining amount of about 50 g (a usable developer amount of 30 g) (electrostatic amount). Capacity reduction) begins. Therefore, the developer remaining amount (%) before that can be displayed as “30% or more” or “100%”.

Next, an embodiment of the operation of detecting the remaining amount of the developer will be described with reference to the flowcharts of FIGS.

The table shown in Table 3 was used as the developer remaining amount correction table 24 used halfway. Also, PA
The empirical value W (0.8 V in this embodiment) based on experimental data accumulation for obtaining the W value is stored in the memory 20 of the image forming apparatus main body A in advance. S401: The power switch of the image forming apparatus main body A is turned on. S402: The control means 22 checks the PAE value in the memory 20. S403: The operation unit 23 determines that the W stored in the memory 20 is
The PAW value is calculated from the value and the PAE value. S404: The main body side developer remaining amount detecting section 25 measures the detected voltage value V3. S405: The control means 22 checks the PAF value in the memory 20. S406: The control means 22 compares the PAF value stored in the memory 20 with the detected voltage value V3, and checks whether the detected voltage value V3 exceeds the PAF value. If “No” is determined, the process proceeds to S 407, where P
The AF value is updated, and the process proceeds to S408. If “Yes” is determined, the process proceeds to S408. S <b> 408: The calculating unit 23 performs the developer remaining amount correction table 24.
Is substituted for F (PAF, PAE, W) to obtain a calculated value, and the control means 22 determines that V3 is F (PAF, PAF).
E, W). If "Yes" is determined, the process proceeds to S411. If “No” is determined, the process proceeds to S 409, where the control unit 22 sends a signal indicating that the remaining amount of the developer is 100% to the display unit 26 of the image forming apparatus main body A, and the control unit 22 transmits the signal to the display unit 26. Display information. Further, the process proceeds to S410, where the developer remaining amount Y (%) value information in the memory 20 is updated. Then, the process returns to S404. S <b> 411: The calculating unit 23 performs the developer remaining amount correction table 24
Is substituted for F (PAF, PAE, W) to obtain a calculated value, and the control means 22 determines that V3 is F (PAF, PAF).
E, W). If “Yes” is determined, the process proceeds to S414. If the determination is "No", the process proceeds to S412, in which the control unit 22 transmits a signal indicating that the remaining amount of the developer is 30% to the display unit 26 of the image forming apparatus main body A, and the control unit 22 transmits the signal to the display unit 26. Display information. Further, the process proceeds to S413, where the developer remaining amount Y (%) value information in the memory 20 is updated. Then, the process returns to S404. S <b> 414: The calculation unit 23 performs the developer remaining amount correction table 24
Is substituted for F (PAF, PAE, W) to obtain a calculated value, and the control means 22 determines that V3 is F (PAF, PAF).
E, W). If "Yes" is determined, the process proceeds to S417. If “No” is determined, the process proceeds to S415, where the control unit 22 sends a signal indicating that the remaining amount of the developer is 25% to the display unit 26 of the image forming apparatus main body A, and the display unit 26 To display that information. Further, the process proceeds to S416, in which the developer remaining amount Y (%) value information in the memory 20 is updated. Then, the process returns to S404. S417 to S431: Similarly, S417, S420, S
If it is determined “Yes” in 423, S426, and S429, Z is sequentially increased in accordance with the developer remaining amount correction table 24 shown in Table 3, and F (PAF, PAE,
W), and the illustrated flowchart is repeated until Z = 0.95. If “No” is determined in each step, the corresponding remaining amount (%) of the developer is displayed, and the remaining amount Y of the developer in the memory 20 is displayed.
(%) Is updated, and the process returns to S404. S <b> 432: The calculating unit 23 performs the developer remaining amount correction table 24
Z = 0.99 is substituted for F (PAF, PAE, W) to obtain a calculated value, and the control means 22 determines that V3 is F (PAF, PAF).
E, W) is checked. If “No” is determined, the process proceeds to S433, in which the control unit 22 transmits a signal indicating that the remaining amount of the developer is 1% to the display unit 26 of the image forming apparatus main body A, and the display unit 26 To display that information. Further, the process proceeds to S434, and the developer remaining amount Y (%) value information in the memory 20 is updated. Then, the process returns to S404. If “Yes” is determined, the process proceeds to S435. S435: The control unit 22 transmits a signal indicating that the remaining amount of the developer is 0% to the display unit 26 of the image forming apparatus main body A, and displays the information on the display unit 26. S436: The control means 22 updates the developer remaining amount Y (%) in the memory 20. S437: End the sequence.

By performing control according to the above-described flowchart, the process cartridge B (PA-a, PA-b) provided with the developer amount detecting devices having different PAE values and PAF values.
When the developer remaining amount display according to the consumption of the developer was evaluated, the process cartridge B was evaluated as shown in FIG.
It was possible to successively detect the remaining amount of the developer amount by absorbing the individual difference of. In FIG. 14, the vertical axis indicates the voltage value V3 detected by the developer amount detecting device, and the horizontal axis indicates the remaining amount display Y (%) of the developer in the developing device C.

Also in this embodiment, similarly to the first embodiment, the process cartridge B can be provided with cartridge identification information (cartridge ID information) for identifying each process cartridge. This is to notify the image forming apparatus main body A that the process cartridge B is different from the previously used process cartridge B when the process cartridge B is replaced.

As means for holding the cartridge ID information (not shown) in the process cartridge B and means for reading the cartridge ID information on the image forming apparatus main assembly A side, those similar to those in the first embodiment can be used.

The cartridge ID information is recognized on the image forming apparatus main body A side and stored in the memory 20 of the image forming apparatus main body A. Further, information relating to the detection of the remaining amount of the developer by the developer amount detecting device, such as the PAE value and the PAF value, is associated with the cartridge ID information.
Is stored in the memory 20.

Thus, even when the process cartridge B in use is removed from the image forming apparatus main body A and replaced, the image forming apparatus main body A is used for the cartridge ID when the process cartridge is used again.
By reading the information (PAE value) stored in the memory 20 of the image forming apparatus main body A corresponding to the cartridge ID, the remaining amount of the developer and the capacitance corresponding to each cartridge are recognized. The relationship between (detection voltage) can be corrected, and the remaining amount of the developer can always be accurately detected.

As described above, according to the present invention, the electrostatic capacity detected by the developer remaining amount detecting means 30 in a state where there is no developer is different for each cartridge depending on the positional relationship of the developer remaining amount detecting means 30 and the like. Further, even when the capacitance detected by the developer remaining amount detecting means 30 is different in a state where the developer is fully charged, the remaining amount of the developer and the detected capacitance (detected voltage value ) Can be corrected, and the remaining amount of the developer can be accurately detected.

According to the present invention, the image forming apparatus main body A
A memory 20 is provided in each of the cartridges, and information necessary for detecting the remaining amount of the developer is stored and used in the memory 20, so that a storage unit is provided in each cartridge, and information necessary for sequentially detecting the remaining amount of the developer is stored therein. The cost can be reduced as compared with the case of causing the cost.

It should be noted that the relationship between the remaining amount of the developer and the detected voltage value greatly differs depending on the cartridge configuration, particularly the configuration and arrangement of the developer remaining amount detecting means. The image forming apparatus is not limited to those illustrated in the embodiments, and implements the present invention.
It can be determined appropriately according to the characteristics of the cartridge.

The resolution for detecting the remaining amount of the developer is not limited to a constant interval over the entire detection range of the remaining amount of the developer.
%, 30%, 20%, 15%, 10%, 8%, 5% ...
The resolution can be increased where the remaining amount of the developer is small. As a matter of course, the finer the interval, the more finely the remaining amount of developer can be displayed.

In each of the above embodiments, the developer remaining amount correction table has been described as being stored in the main body control section. However, it is also possible to store this in the memory of the image forming apparatus main body.

In each of the above embodiments, the capacitance detected by the developer remaining amount detecting means and the detection voltage finally detected by the developer amount detecting device based on the output of the developer remaining amount detecting means are reduced. The case where the increasing relationship is set to be reversed has been described, but the relationship between the capacitance and the voltage varies depending on the detection circuit provided in the image forming apparatus, and the relationship between the capacitance and the voltage decreases by the same amount. It may be a function or an increasing function.

The expression method of the remaining amount of the developer is represented by (%) such as a ratio of the currently usable developer to the initial amount of the usable developer, a ratio of the developer to a so-called full state, or (g). ) Not limited to the notation, for example,
As other display methods, various notation methods can be used, such as how many remaining prints are possible in a more advanced form.

The display on the display means is not limited to the value display. For example, the display may be displayed as a gas gauge type indicating a scale with a needle, a bar graph type indicating the length of an expanding / contracting bar, or the like. Further, for example, information about the remaining amount of the developer, such as a warning message indicating that there is no developer, may be notified by voice, or may be recorded on a recording medium and output. In this manner, any display method may be used as long as the user can know the remaining amount of the developer.

Further, the display of the remaining amount of the developer is not limited to the display means provided in the main body of the image forming apparatus. It can also be performed by a display means which is a screen of a device such as a host computer.

In each of the above embodiments, the plate antenna system based on the measurement of the capacitance is used as the developer remaining amount detecting means. However, the present invention is limited to the developer remaining amount detecting means of this system. However, the method is not particularly limited as long as the developer amount level can be detected. or,
In each of the above embodiments, the developer remaining amount detecting means is provided in the developing chamber. As a result, the detection accuracy of the specific portion is improved, and more accurate detection of the remaining amount of the developer can be performed. However, the present invention is not limited to this. A plurality of developer remaining amount detecting means may be provided for improving accuracy.For example, a developer remaining amount detecting means is provided in the developer accommodating container. It is also possible to adopt a configuration in which the remaining amount of the developer is sequentially detected in a range until the image is reduced so that a predetermined quality image cannot be formed.

Further, in each of the above embodiments, the cartridge that can be attached to and detached from the image forming apparatus main body A is described as the process cartridge B, but the present invention is not limited to this. That is, as shown in FIG. 15, the present invention also suitably works when the developing device C is a cartridge that can be attached to and detached from the image forming apparatus main body. FIG.
5, a developing device C includes a developing chamber 5A for holding a developing unit 5 such as a developing roller 5a and a developing blade 5c, and a developer container 4 for storing a developer to be supplied to the developing unit 5.
Are integrally formed by a developer frame 9 and a development frame 10 made of plastic to form a cartridge. The developing device C is obtained by unitizing the developing device components of the process cartridge B described in the first and second embodiments. That is, the photosensitive drum 1, the charging unit 2, and the cleaning unit 7 are removed from the process cartridge B. Can be considered as an integrated cartridge. Therefore,
All the configurations of the developing device and the developer amount detecting device described in the first and second embodiments are similarly applied to the developing device C of the present embodiment. Therefore, for the description of these configurations and operations, the above description performed in Embodiments 1 and 2 is cited.

[0142]

As described above, according to the present invention,
A cartridge including a developer container, a developing unit, and a developer remaining amount detecting unit capable of sequentially outputting an output corresponding to the amount of the developer, an image forming apparatus to which the cartridge is detachable, and an image using the cartridge The forming system includes a developer sealing member that is opened at the start of use of the cartridge between the developer accommodating container of the cartridge and the developing unit, and the developer is sealed in the apparatus main body before the developer sealing member is opened. Information corresponding to the value output by the remaining amount detection means is configured to be stored in a storage means provided in the apparatus main body,
Based on the information corresponding to the value output by the developer remaining amount detecting means in the apparatus main body before the developer sealing member stored in the storage means is opened, and the output of the developer remaining amount detecting means, Since it is configured to detect the amount of developer in the cartridge,
By accurately detecting the remaining amount of the developer and notifying the user of the remaining amount, a so-called blank image is not generated before a warning is issued to the user. It is possible to notify the user of an appropriate cartridge replacement time (purchase time), such as minimizing the remaining amount of the developer at the time when the occurrence of the warning is warned.

In the main body of the image forming apparatus, an output value in a state where there is no developer in at least the detection area of the developer remaining amount detecting means is measured, and the measured output value is used. And corrects the relationship between the output value of the developer remaining amount detecting means and the remaining amount of the developer so that the amount of the remaining developer can be accurately detected, and the user can be notified of the remaining amount of the developer accurately. can do. Further, the cost can be reduced by providing a storage unit for storing information used for detecting the remaining amount of the developer in the image forming apparatus.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a process cartridge and an image forming apparatus according to the present invention.

FIG. 2 is an enlarged sectional view of the process cartridge of FIG.

FIG. 3 is a circuit configuration diagram of an embodiment of a developer amount detection device.

FIG. 4 is a schematic diagram illustrating a relationship between a cartridge and an image forming apparatus main body for describing an embodiment of a control configuration of a memory included in the image forming apparatus main body.

FIG. 5 is a graph illustrating a relationship between a detection voltage value of a developer amount detection device and a remaining amount of the developer.

FIG. 6 is a longitudinal sectional view of a developer sealing member.

FIG. 7 is a flowchart of a PAE value storage operation according to the present invention.

FIG. 8 is a flowchart illustrating an embodiment of a developer amount detection operation using a storage unit of the image forming apparatus main body according to the present invention.

FIG. 9 is a graph illustrating a developer remaining amount display after correcting a detection voltage value of a developer amount detection device according to an embodiment of the present invention.

FIG. 10 is a schematic relationship diagram between a cartridge and an image forming apparatus main body for describing another embodiment of a control configuration of a memory provided in the image forming apparatus main body.

FIG. 11 is a flow chart for explaining another embodiment of the developer amount detecting operation using the storage means of the image forming apparatus main body according to the present invention.

FIG. 12 is a flowchart similar to FIG. 11, but showing a procedure following the flowchart of FIG. 11;

FIG. 13 is a flowchart similar to FIG. 11, showing a procedure following the flowchart of FIG. 12;

FIG. 14 is a graph for explaining a remaining developer amount display after correcting a detection voltage value of a developer amount detecting device according to another embodiment of the present invention.

FIG. 15 is a cross-sectional view of an embodiment of a developing device formed into a cartridge to which the present invention can be applied.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 photosensitive drum 2 charging means 3 laser scanner 4 developer storage container 5 developing means 5 a developing roller (developer carrier) 5 A developing chamber 7 cleaning device 15 fixing means 20 storage means (memory) 21 main body control unit 26 display means 30 Developer residual amount detecting means 31 First sheet metal (plate antenna) 32 Second sheet metal (plate antenna) 100 Laser beam printer (printer) A Image forming apparatus main body (apparatus main body) B Process cartridge C Developing device (developing unit), developing cartridge

Continued on the front page (72) Inventor Hideki Matsumoto 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2H027 DA27 DD02 DE07 EE08 EJ08 EJ15 GB03 HA03 HB13 2H071 BA03 BA04 BA33 DA06 DA08 DA13 DA15 2H077 AA01 AA07 BA09 DA15 DA24 DA34 DA59

Claims (25)

[Claims] An image forming apparatus in which a cartridge including a developer storage container, a developing unit, and a developer remaining amount detecting unit capable of sequentially outputting an output corresponding to an amount of the developer is detachable. A developer sealing member that is opened at the start of use of the cartridge is provided between the developer storage container and the developing unit, and the developer is opened in the apparatus main body before the developer sealing member is opened. An image forming apparatus, wherein information corresponding to a value output by a remaining amount detecting unit is stored in a storage unit provided in the apparatus main body. 2. The apparatus according to claim 1, further comprising: information corresponding to a value output by said developer remaining amount detection means in said apparatus main body before said developer sealing member stored in said storage means is opened. 2. The image forming apparatus according to claim 1, wherein an amount of the developer in the cartridge is detected based on an output of the amount detecting unit. 3. An amount of change in an output value of the developer remaining amount detecting means from a value output by the developer remaining amount detecting means in the apparatus main body before the developer sealing member is opened. 3. The image forming apparatus according to claim 2, wherein the amount of the developer is detected based on the detected amount. 4. An amount of change in an output value of the developer remaining amount detecting unit from a value output by the developer remaining amount detecting unit in the apparatus main body before the developer sealing member is opened. 4. The image forming apparatus according to claim 3, wherein the amount of the developer is detected using a table in which at least the amount of the developer is associated. 5. The image forming apparatus according to claim 2, wherein said storage means stores information corresponding to an output value when said developer remaining amount detection means detects the maximum amount of developer. . 6. The information stored in said storage means, the information corresponding to a value output by said developer remaining amount detection means in said apparatus main body before said developer sealing member is opened, and said storage means Based on the stored information corresponding to the output value when the developer remaining amount detecting means detects the maximum amount of the developer and the output of the developer remaining amount detecting means, the amount of developer in the cartridge is determined. The image forming apparatus according to claim 5, wherein: 7. An amount of developer remaining in the apparatus main body before the developer sealing member is opened from an output value when the developer remaining amount detecting means detects the maximum amount of developer. The absolute value of the value obtained by subtracting the value output by the means and the predetermined value is used as a developer use range, and the output value when the developer remaining amount detecting means detects the maximum amount of developer within the use range is corrected. 7. The image forming apparatus according to claim 6, wherein the amount of the developer is obtained from a relationship between the value multiplied by the value and the remaining amount of the developer. 8. The apparatus according to claim 1, wherein the developer sealing member is automatically opened when the cartridge is started to be used in a state where the cartridge is mounted on the apparatus main body.
8. The image forming apparatus according to any one of items 7 to 7. 9. The cartridge further holds cartridge identification information, and the apparatus main body further reads the cartridge identification information of the mounted cartridge,
The image forming apparatus according to claim 1, further comprising a unit configured to store the image in the storage unit. 10. The method according to claim 1, wherein the developer remaining amount detecting unit outputs a signal obtained by measuring a capacitance between at least two electrodes. The image forming apparatus as described in the above. 11. The apparatus according to claim 2, wherein the apparatus main body further includes a unit for outputting a signal for displaying any one of the information on the detected amount of the developer. Image forming apparatus. 12. The image according to claim 11, wherein the apparatus main body further includes a display unit, and a signal for displaying information on the detected amount of the developer is transmitted to the display unit and displayed. Forming equipment. 13. The apparatus main body is further communicable with a device having a display means, and transmits a signal for displaying information on the detected amount of the developer to the device having the display means. The image forming apparatus according to claim 11. 14. An electrophotographic photoreceptor, a charging unit for charging the electrophotographic photoreceptor, a developing unit for supplying a developer to the electrophotographic photoreceptor, and a cleaning unit for cleaning the electrophotographic photoreceptor. The image forming apparatus according to claim 1, wherein the image forming apparatus has at least one of them. 15. A cartridge detachably mountable to an image forming apparatus, comprising: a developer storage container; a developing unit; and a developer remaining amount detecting unit capable of sequentially outputting an output corresponding to a developer amount. Providing a developer sealing member that is opened at the start of use of the cartridge between the developer accommodating container and the developing means, and performing the developing in the apparatus main body before the developer sealing member is opened. A cartridge according to claim 1, wherein information corresponding to a value output by said remaining amount detecting means is stored in a storage means provided in said image forming apparatus main body. 16. The image forming apparatus main body outputs the developer remaining amount detecting means in the image forming apparatus before the developer sealing member is opened based on the information stored in the storage means. 16. The cartridge according to claim 15, wherein the amount of the developer in the cartridge is detected by correcting a result obtained by associating a value with an output value of the developer remaining amount detecting unit with a correcting unit. . 17. The information corresponding to an output value when the developer remaining amount detecting means detects the maximum amount of the developer,
17. The cartridge according to claim 15, wherein the cartridge is stored in the storage unit provided in the image forming apparatus main body. 18. The image forming apparatus main body outputs the developer remaining amount detecting means in the image forming apparatus before the developer sealing member is opened based on the information stored in the storage means. A value, an output value when the developer remaining amount detecting means detects the maximum amount of the developer based on the information stored in the storage means, and an output value of the developer remaining amount detecting means. 18. The cartridge according to claim 17, wherein the amount of the developer in the cartridge is detected by correcting a result of the processing by a correction unit. 19. The developer sealing member according to claim 15, wherein the developer sealing member is automatically opened at the start of use of the cartridge in a state where the cartridge is mounted on the image forming apparatus main body. The cartridge according to the item. 20. The image forming apparatus according to claim 15, wherein said image forming apparatus main body has means for holding cartridge identification information capable of identifying an individual cartridge when mounted on said image forming apparatus main body. 20. The cartridge according to any one of items 19 to 19. 21. The apparatus according to claim 15, wherein said developer remaining amount detecting means outputs a signal obtained by measuring a capacitance between at least two electrodes.
The cartridge according to any one of the above items. 22. An electrophotographic photosensitive member, charging means for charging the electrophotographic photosensitive member, developing means for supplying a developer to the electrophotographic photosensitive member, and cleaning means for cleaning the electrophotographic photosensitive member. The cartridge according to any one of claims 15 to 21, wherein the cartridge has at least one of them. 23. An image forming system for forming an image on a recording medium by using a cartridge detachable from a main body of the image forming apparatus, comprising: (a) a developer container, a developing unit, and a signal corresponding to a developer amount. A cartridge having: a developer remaining amount detecting means capable of sequentially outputting the toner; and a developer sealing member provided between the developer accommodating container and the developing means and opened when the cartridge is started to be used. b) storage means for storing information corresponding to a value output by the developer remaining amount detection means in the apparatus main body before the developer sealing member is opened, and stored in the storage means; Calculation processing for associating a value output by the developer remaining amount detecting means in the image forming apparatus with an output value of the developer remaining amount detecting means in the image forming apparatus before the developer sealing member is opened based on information. Correct the result Image forming system characterized by and a control means for detecting the amount of developer within the cartridge by correcting the stage. 24. The storage unit further stores information corresponding to an output when the developer remaining amount detecting unit detects the maximum remaining amount of the developer, and the control unit stores the information in the storage unit. The value output by the developer remaining amount detecting means in the image forming apparatus before the developer sealing member is opened based on the received information, and the developer remaining amount based on the information stored in the storage means. The output value when the amount detecting means detects the maximum amount of the developer and the output value of the developer remaining amount detecting means are associated with each other, and the result of calculation processing is corrected by the correcting means. The image forming system according to claim 23, wherein the amount of the agent is detected. 25. The apparatus according to claim 2, further comprising display means for displaying information relating to the detected amount of developer.
The image forming system according to 3 or 24.